Inter-rat coverage determination for energy saving management

ABSTRACT

Embodiments of systems and techniques are described for determining inter-radio access technology (inter-RAT) coverage for energy saving management (ESM). In some embodiments, a network management (NM) apparatus may determine that a source cell of a network of a first RAT is triggered to activate an energy saving state and that the source cell is partially overlapped by each of a plurality of cells of one or more networks of one or more RATs different from the first RAT. The NM apparatus may instruct the source cell to activate the energy saving state when a combination of the plurality of cells provides coverage of the source cell. Other embodiments may be described and claimed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/903,284, entitled “INTER-RAT COVERAGE DETERMINATION FOR ENERGY SAVINGMANAGEMENT,” filed Feb. 23, 2018, which is a continuation of U.S. patentapplication Ser. No. 15/003,299, entitled “INTER-RAT COVERAGEDETERMINATION FOR ENERGY SAVING MANAGEMENT,” filed Jan. 21, 2016, issuedas U.S. Pat. No. 9,942,841 on Apr. 10, 2018, which is a continuation ofU.S. patent application Ser. No. 14/753,669, entitled “INTER-RATCOVERAGE DETERMINATION FOR ENERGY SAVING MANAGEMENT,” filed Jun. 29,2015, issued as U.S. Pat. No. 9,288,755 on Mar. 15, 2016, which is acontinuation of U.S. patent application Ser. No. 14/104,633, entitled“INTER-RAT COVERAGE DETERMINATION FOR ENERGY SAVING MANAGEMENT,” filedDec. 12, 2013, issued as U.S. Pat. No. 9,100,911 on Aug. 4, 2015, whichclaims priority to U.S. patent application Ser. No. 13/730,248, entitled“Inter-Rat Coverage Determination for Energy Saving Management” filedDec. 28, 2012, issued as U.S. Pat. No. 8,805,384 on Aug. 12, 2014, whichclaims priority to U.S. Provisional Patent Application No. 61/639,795,entitled “Advanced Wireless Communication Systems and Techniques” filedApr. 27, 2012; the contents of each of which are hereby incorporated byreference in their entireties herein.

TECHNICAL FIELD

The present disclosure relates generally to wireless communication, andmore particularly, to systems and techniques for inter-radio accesstechnology (inter-RAT) coverage determination for energy savingmanagement (ESM).

BACKGROUND

ESM techniques have been deployed in wireless communications systems toswitch off components (such as Third Generation Partnership Project LongTerm Evolution (3GPP LTE) or other “hot spot” cells) that are lightlyused at off-peak hours. When such components are switched off, legacywireless communication system cells may be relied on to provide servicesto subscribers. Examples of such legacy system cells may includeuniversal mobile telecommunications system terrestrial radio accessnetwork (UTRAN) cells or global system for mobile communicationsenhanced data rates for global system for mobile communication evolvedradio access networks (GERAN) cells. Existing ESM techniques typicallyassume that the coverage of a legacy cell will wholly encompass a hotspot cell, and thus that the coverage of a switched-off hot spot cellcan be taken over by a single legacy cell. When this assumption fails,existing ESM techniques may prevent legacy cell-covered components fromswitching off, resulting in wasted energy.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be readily understood by the following detaileddescription in conjunction with the accompanying drawings. To facilitatethis description, like reference numerals designate like structuralelements. Embodiments are illustrated by way of example, and not by wayof limitation, in the figures of the accompanying drawings.

FIG. 1 illustrates an environment in which a cell of a first RAT iscovered by a combination of two cells of RATs different from the firstRAT, in accordance with various embodiments.

FIGS. 2A and 2B are block diagrams illustrating example ESM integrationreference point (IRP) manager and agent modules, respectively, inaccordance with various embodiments.

FIG. 3 is a block diagram illustrating an example system for inter-RATESM, in accordance with various embodiments.

FIG. 4 is a flow diagram of a first example inter-RAT ESM process, inaccordance with various embodiments.

FIG. 5 is a flow diagram of a second example inter-RAT ESM process, inaccordance with various embodiments.

FIG. 6 is a block diagram of an example computing device suitable forpracticing the disclosed embodiments, in accordance with variousembodiments.

DETAILED DESCRIPTION

Embodiments of systems and techniques are described for determininginter-RAT coverage for ESM. In some embodiments, a network management(NM) apparatus may determine that a source cell of a first RAT istriggered to activate an energy saving state (ESS) and that the sourcecell is partially overlapped by each of a plurality of cells of one morenetworks of one or more RATs different from the first RAT. The NMapparatus may instruct the source cell to activate the ESS when acombination of the plurality of cells provides coverage of the sourcecell. Other embodiments may be described and claimed.

The systems and techniques disclosed herein may decrease energyconsumption in wireless communication networks by allowing source cellsto go into an ESS when they are covered by a combination of multiplecells of a different RAT. The systems and techniques disclosed hereinmay also improve resource management in multi-RAT environments byidentifying which cells are covered by a combination of multiple cellsof other RATs and thereby providing a more complete picture of coverageacross the multiple RATs. The present disclosure may be particularlyadvantageous in self-organizing network (SON) applications, includingthose in which network optimization is centralized in one or more NMapparatus or other devices.

In the following detailed description, reference is made to theaccompanying drawings which form a part hereof wherein like numeralsdesignate like parts throughout, and in which is shown by way ofillustration embodiments that may be practiced. It is to be understoodthat other embodiments may be utilized and structural or logical changesmay be made without departing from the scope of the present disclosure.Therefore, the following detailed description is not to be taken in alimiting sense, and the scope of embodiments is defined by the appendedclaims and their equivalents.

Various operations may be described as multiple discrete actions oroperations in turn, in a manner that is most helpful in understandingthe claimed subject matter. However, the order of description should notbe construed as to imply that these operations are necessarily orderdependent. In particular, these operations may not be performed in theorder of presentation. Operations described may be performed in adifferent order than the described embodiment. Various additionaloperations may be performed and/or described operations may be omittedin additional embodiments.

For the purposes of the present disclosure, the phrases “A and/or B” and“A or B” mean (A), (B), or (A and B). For the purposes of the presentdisclosure, the phrase “A, B, and/or C” means (A), (B), (C), (A and B),(A and C), (B and C), or (A, B and C).

The description may use the phrases “in an embodiment,” or “inembodiments,” which may each refer to one or more of the same ordifferent embodiments. Furthermore, the terms “comprising,” “including,”“having,” and the like, as used with respect to embodiments of thepresent disclosure, are synonymous.

As may be used herein, the term “module” may refer to, be part of, orinclude an Application Specific Integrated Circuit (ASIC), an electroniccircuit, a processor (shared, dedicated, or group) and/or memory(shared, dedicated, or group) that execute one or more software orfirmware programs, a combinational logic circuit, and/or other suitablecomponents that provide the described functionality.

Referring now to FIG. 1, an environment 100 is illustrated in which anumber of cells 102, 104, 106 and 108 of a first RAT variously overlapwith cells 110 and 112 of one or more RATs different than the first RAT.For example, cells 102, 104, 106 and 108 may be E-UTRAN cells, whilecell 110 may be a UTRAN cell and cell 112 may be a GERAN cell.

In some embodiments, cell 102 may be triggered to activate an ESS. Priorto the trigger, cell 102 may not be in an ESS, and may instead be in adefault state that is configured to handle normal or peak trafficsituations. In an ESS, some functions or resources of cell 102 may beswitched off or otherwise restricted. The specific functions orresources restricted, and the degree of restriction, may vary by celltype and usage history, among other variables. The ESS associated withcell 102 may be such that cell 102 can no longer provide wirelesscommunication service to user equipment (UE) previously served by cell102. For example, an evolved nodeB (eNB) associated with cell 102 orother related circuitry (such as an antenna) may be transitioned to alow power state. In an ESS, cell 102 may not be visible to any UEs inits nominal coverage area. In order to avoid service disruptions, insome embodiments, the coverage area of cell 102 must be covered by oneor more other cells to which the UE may be offloaded before cell 102 maybe allowed to activate an ESS.

In environment 100, no one of the other first RAT cells 104, 106 and 108may cover cell 102, nor may any combination of first RAT cells 104, 106and 108. Thus, it may not be possible for the UE currently served bycell 102 to be offloaded via intra-RAT transfer. Additionally, neithercell 110 nor cell 112 (of one or more networks of one or more RATsdifferent from the first RAT associated with cell 102) individually maycover cell 102. However, cells 110 and 112 may cover cell 102 when cells110 and 112 are taken together. In some embodiments, upon adetermination that two or more cells of a RAT different from the firstRAT cover cell 102, the UE originally served by cell 102 may beoffloaded to cells 110 and 112 via an inter-RAT handover and cell 102may activate an ESS. The distribution of traffic from the source cell tocells 110 and 112 may be based on the traffic loads of cells 110 and 112(e.g., to balance the loads on cells 110 and 112), for example.Additional embodiments are described herein.

Referring now to FIGS. 2A and 2B, block diagrams of example ESMintegration reference point (IRP) manager module 200 and agent module250 are illustrated, respectively, in accordance with variousembodiments. In some embodiments, the inter-RAT ESM processes describedherein may be performed in whole or in part by interactions between ESMintegration IRP manager module 200 and ESM IRP agent module 250. In someembodiments, ESM IRP agent module 250 may encapsulate a set of ESMfunctions for one or more network elements (NEs). NEs may includecommunication system entities that may include one or more devices.Examples of NEs may include eNBs, UEs, switches, routers, or any othercommunication system component. ESM IRP agent module 250 may beintegrated with an NE, or integrated with a computing device separatefrom the NE. In some embodiments, ESM IRP manager module 200 may useinformation provided by one or more ESM IRP agents (such as ESM IRPagent module 250) for any of a number of applications, includingconfiguring trigger conditions for ESS transitions for different NEs. Anumber of functions that may be performed by ESM IRP manager module 200are described herein.

ESM IRP manager module 200 and/or agent module 250 may be included atany of a number of different levels in a wireless communication system(such as a network management (NM) level or an element management (EM)level) in any of a number of different apparatuses. For example, in somewireless communication systems, ESM processes may be centralized at theNM level in one or more NM apparatuses; in such systems, ESM IRP managermodule 200 may provide instructions to NEs in the system to move to anESS and set trigger conditions under which NEs may transition to an ESS,while ESM IRP agent module 250 may provide condition information to ESMIRP manager module 200 and receive instructions for certain NEs totransition to an ESS. In some wireless communication system, ESMprocesses may be centralized at the EM level (e.g., in one or more EMapparatuses) or distributed among NEs; in such systems, ESM IRP managermodule 200 may set trigger conditions under which NEs may transition toan ESS, while ESM IRP agent module 250 may use these trigger conditionsto control ESM functions within the NEs.

Various components of ESM IRP manager module 200 and ESM IRP agentmodule 250 are now discussed with reference to FIGS. 2A and 2B. Thecomponents illustrated in FIGS. 2A and 2B are examples, and any one ormore components may be omitted, or additional components included, inaccordance with the disclosed embodiments. In some embodiments, a singleNE includes at least some of the functionality of both ESM IRP managermodule 200 and ESM IRP agent module 250 and may make ESM decisionsautonomously.

Referring to FIG. 2A, illustrative components of ESM IRP manager module200 are shown. ESM IRP manager module 200 may include trigger module202. Trigger module 202 may be configured to determine that source cellof a first RAT is triggered to activate an ESS. As discussed above, anESS may be a state in which some functions of the source cell arerestricted in resource usage. In some embodiments, the source cell maybe triggered when one or more operating conditions (constituting atrigger point) are met. For example, the source cell may be triggeredwhen the load on the source cell crosses below a load threshold, whenthe loads on neighboring cells remain below certain load thresholds,when the time of day is one in which ES techniques are allowed to beimplemented (e.g., at night), whether the first RAT is prioritized forESM over one or more other RATs monitored by ESM IRP manager module 200,or any combination of such conditions. In some embodiments, the networkof the first RAT may be an E-UTRAN. In some embodiments, the network ofthe first RAT may be an UTRAN. In some embodiments, trigger module 202may be configured to determine whether the source cell (e.g., an eNBserving the source cell) supports inter-RAT ES (e.g., whether the sourcecell includes modules providing one or more inter-RAT ES functions).This determination may occur before, after, or as part of thedetermination of whether the source cell is triggered to activate anESS.

In some embodiments in which ESM IRP manager module 200 is included atan EM-level, such as with an eNB, trigger module 202 may be configuredto determine when operating conditions within the source cell havereached a trigger point at which the source cell should activate an ESS.In some embodiments, ESM IRP manager module 200 may be included at anNM-level.

ESM IRP manager module 200 may include an overlap module 204. Overlapmodule 204 may be configured to determine whether a source cell ispartially overlapped by each of a plurality of cells of one or morenetworks of one or more RATs different from the first RAT (i.e., the RATof the source cell). In some embodiments, the one or more networks ofthe one or more RATs different from the first RAT may include a UTRANand/or a GERAN. For example, an E-UTRAN source cell may be overlapped byUTRAN and/or GERAN cells in environments in which the source cellprovides capacity enhancement to, but does not cover, the UTRAN and/orGERAN cells (e.g., as illustrated by first RAT cell 102 with respect toother RAT cells 110 and 112 of FIG. 1). In some embodiments, a firstportion of an E-UTRAN source cell may be covered by one UTRAN or GERANcell, a second portion of the E-UTRAN source cell may be covered byanother UTRAN or GERAN cell, and a third portion of the E-UTRAN sourcecell may be covered by both UTRAN or GERAN cells.

Overlap module 204 may be further configured to determine whether theplurality of cells partially overlapping the source cell providescoverage of the source cell. Coverage may be complete coverage,substantially complete coverage, or sufficient coverage, for example. Insome embodiments, overlap module 204 may store a value of anenergy-saving-coverage (ES-coverage) attribute for each target cellproximate to a source cell. In some embodiments, a target cell may beadjacent to a source cell. The value of the ES-coverage attribute mayindicate whether and how the target cell may serve as a candidate cellfor taking over coverage for the source cell if the source cellactivates an ESS. In some embodiments, a value for an ES-coverageattribute may be defined between each pair of cells.

For example, in some embodiments, an ES-coverage attribute for an targetcell (relative to a source cell) may take one of three values: “yes,”“partial” and “no.” A value of “yes” may indicate that the target cellis recommended to be considered as a candidate cell to take overcoverage when the source cell is about to transferred to an ESS. A valueof “partial” may indicate that the target cell is recommended along withat least one other target cell to be considered as an entirety ofcandidate cells to take over coverage when the source cell is about tobe transferred to an ESS. A value of “no” may indicate that the targetcell is not recommended to be considered as a candidate cell to takeover coverage when the source cell is about to be transferred to an ESSnor is the target cell recommended along with at least one other targetcell to be considered as an entirety of candidate cells to take overcoverage when the source cell is about to be transferred to an ESS.

To illustrate one implementation of such ES-coverage attributes, Table 1provides a list of an attribute labeled “IsESCoveredBy” for the cellsillustrated in FIG. 1. The italicized entries in Table 1 indicateinter-RAT ES-coverage attributes (for the purposes of Table 1, anembodiment is considered in which cell 110 and cell 112 are of one ormore networks of the same RAT, such as a UTRAN or a GERAN.

TABLE 1 Values of ES-coverage attribute IsESCoveredBy for various sourceand target cells of FIG. 1. ES-coverage attribute Value Cell 102IsESCoveredBy Cell 104 Partial Cell 102 IsESCoveredBy Cell 106 PartialCell 102 IsESCoveredBy Cell 108 No Cell 102 IsESCoveredBy Cell 110Partial Cell 102 IsESCoveredBy Cell 112 Partial Cell 104 IsESCoveredByCell 102 Partial Cell 104 IsESCoveredBy Cell 106 Partial Cell 104IsESCoveredBy Cell 108 No Cell 104 IsESCoveredBy Cell 110 Yes Cell 104IsESCoveredBy Cell 112 No Cell 106 IsESCoveredBy Cell 102 Partial Cell106 IsESCoveredBy Cell 104 Partial Cell 106 IsESCoveredBy Cell 108 NoCell 106 IsESCoveredBy Cell 110 Yes Cell 106 IsESCoveredBy Cell 112 NoCell 108 IsESCoveredBy Cell 102 No Cell 108 IsESCoveredBy Cell 104 NoCell 108 IsESCoveredBy Cell 106 No Cell 108 IsESCoveredBy Cell 110 NoCell 108 IsESCoveredBy Cell 112 Yes Cell 110 IsESCoveredBy Cell 102Partial Cell 110 IsESCoveredBy Cell 104 Partial Cell 110 IsESCoveredByCell 106 Partial Cell 110 IsESCoveredBy Cell 108 No Cell 110IsESCoveredBy Cell 112 No Cell 112 IsESCoveredBy Cell 102 Partial Cell112 IsESCoveredBy Cell 104 No Cell 112 IsESCoveredBy Cell 106 No Cell112 IsESCoveredBy Cell 108 Partial Cell 112 IsESCoveredBy Cell 110 No

A number of techniques which may be executed by overlap module 204 toidentify and store information about overlapping relationships between asource cell and proximate target cells, including techniques for storingES-coverage attributes, are described below with reference to FIG. 4.

ESM IRP manager module 200 may include instruction module 206.Instruction module 206 may be configured to instruct a source cell orother NE to activate an ESS. In some embodiments, instruction module 206may only provide such an instruction when sufficient triggerdeterminations have been made by trigger module 202 and sufficientoverlap determinations have been made by overlap module 204. In someembodiments, instruction module 206 may be configured to instruct thesource cell to deactivate an ESS. An instruction to deactivate an ESSmay be based on, for example, a traffic load of one or more of the otherRAT cells to which the source cell's traffic was offloaded (e.g., whenone of the other RAT cells becomes overburdened), or based on anoperational status of one or more of the other RAT cells (e.g., when oneor more of the other RAT cells experiences an operational failure).

ESM IRP manager module 200 may include notification module 208.Notification module 208 may be configured to transmit a notificationmessage, for display to a network operator (e.g., on a visual displaydevice), when the source cell has activated an ESS. In some embodiments,notification module 208 may be configured to notify an NM-levelcomponent when an eNB or other device related to the source cell hasactivated an ESS. In some embodiments, notification module 208 may beconfigured to notify an NM-level or EM-level component, for example, ofthe identities of the plurality of other RAT cells that provide coverageof the source cell (e.g., by providing cell identifiers for cells 110and 112 when cell 102 enters an ESS in FIG. 1). Notification module 208may configure a desired notification schedule for ES-function relatedinformation (such as load on NEs) and transmit the notification scheduleto ESM IRP agent modules (such as ESM IRP agent module 250).Notification module 208 may receive such ES-function related informationfrom ESM IRP agent modules (e.g., activation and deactivation of ESS fornetwork elements for which the ESM IRP agent is responsible).

Referring to FIG. 2B, illustrative components of ESM IRP agent module250 are shown. ESM IRP agent module 250 may include energy consumptionmodule 252. In some embodiments, energy consumption module 252 may beconfigured to provide information about the energy consumption of NEs toESM IRP manager module 200. In some embodiments, energy consumptionmodule 252 may be configured to receive information about energyconsumption from the NEs themselves, and/or aid ESM IRP manager module200 in accessing this information from the NEs. Energy consumptioninformation may be used to determine appropriate thresholds foractivating and deactivating ESSs, and determining when these thresholdshave been met, for example.

ESM IRP agent module 250 may include state module 254. In someembodiments, state module 254 may be configured to provide informationto ESM IRP manager 200 about the current state of NEs for which ESM IRPagent module 250 is responsible. Example states include an ESS, adefault (non-ESS) state, a compensating state (in which the NE iscompensating for one or more other NEs that have activated their ownESS), or a number of other states relating to the activation ordeactivation of ES functions. In some embodiments, state module 254 maybe configured to store state information in a memory.

ESM IRP agent module 250 may include notification module 256. In someembodiments, notification module 256 may be configured to provide anotification to ESM IRP manager module 200 when the source cell hasactivated an ESS (e.g., by pushing a notification or responding to aquery for a notification). Notification module 256 may receive a desirednotification schedule for ES-function related information from ESM IRPmanager module 200. Notification module 256 may provide ES-functionrelated information, such as activation and deactivation of ESS for NEsfor which ESM IRP agent module 250 is responsible.

Referring now to FIG. 3, a block diagram of an example system 300 forinter-RAT ESM is illustrated, in accordance with various embodiments. Asdiscussed above, an ESM IRP manager module (such as ESM IRP managermodule 200 of FIG. 2) and/or an ESM IRP agent module (such as ESM IRPagent module 250 of FIG. 2) may be implemented in any of a number oflevels and components within a wireless communication system. Exemplaryimplementations of ESM IRP manager modules and ESM IRP agent modules areindicated in FIG. 3, but all implementations are only illustrative andany one or more implementations may be omitted while others may beincluded.

System 300 may be configured to support networks of one or more RATs,such as an E-UTRAN. In some embodiments, the RAT(s) supported by system300 may include the first RAT of cells 102, 104, 106 and 108 inenvironment 100, and/or the RATs of cells 110 and 112 (FIG. 1). System300 may be configured to deliver any of a number of services, such asmultimedia delivery over HTTP, live streaming over RTP, conversationalservices (e.g., video conferencing), and TV broadcasting, for example.System 300 may include other wireless personal area network (WPAN),wireless local area network (WLAN), wireless metropolitan area network(WMAN), and/or wireless wide area network (WWAN) devices such as networkinterface devices and peripherals (e.g., network interface cards(NICs)), access points (APs), redistribution points, end points,gateways, bridges, hubs, etc. to implement a cellular telephone system,a satellite system, a personal communication system (PCS), a two-wayradio system, a one-way pager system, a two-way pager system, a personalcomputer (PC) system, a personal data assistant (PDA) system, a personalcomputing accessory (PCA) system, and/or any other suitablecommunication system.

System 300 may include an NM apparatus 302. In some embodiments, NMapparatus 302 may monitor the components of system 300 and collectmeasurements of their performance and the relationships between thecomponents. Based on the analysis of these measurements andrelationships, NM apparatus 302 may identify potential problems andimprovements in the configuration and operation of the components ofsystem 300, and may implement changes to system 300.

NM apparatus 302 may include receiver/transmitter module 322.Receiver/transmitter module 322 may be configured for receiving andtransmitting signals to and from other devices by wired or wirelessconnections. For example, receiver/transmitter module 322 may beconfigured to receive signals from or transmit signals to an elementmanager (EM) component of an eNB (such as eNB 308), a base station (suchas any of base stations 310 and 312), a domain management (DM) apparatus304 (which may provide management functions for a domain or otherportion of system 300, and may itself include an ESM IRP manager moduleand/or an ESM IRP agent module, not shown), or any other suitablyconfigured devices. In some embodiments, NM apparatus 302 maycommunicate with an eNB via a wired connection. In some embodiments,receiver/transmitter module 322 may include separate receiver circuitryand transmitter circuitry. In embodiments in which receiver/transmittermodule 322 is configured for wireless communications, it may include,for example, one or more directional or omni-directional antennas (notshown) such as dipole antennas, monopole antennas, patch antennas, loopantennas, microstrip antennas, and/or other types of antennas suitablefor reception of radio frequency (RF) or other wireless communicationsignals.

NM apparatus 302 may include an ESM IRP manager module 324. ESM IRPmanager module 324 may take any of the forms described above withreference to ESM IRP manager module 200 (FIG. 2). ESM IRP manager module324 may be coupled with receiver/transmitter module 322. Additionalcomputing device components, such as one or more processors, memory,input/output (I/O) components and displays, may be included with NMapparatus 302. Additionally, the functions of NM apparatus 302 may bedistributed across multiple computing devices.

System 300 may include one or more eNBs, such as eNB 308. System 300 mayalso include one or more base stations, such as base stations 310 and312. In some embodiments, one or more of base stations 310 and 312include eNBs. eNB 308 and base stations 310 and 312 may include a numberof components; for ease of illustration, only the components of eNB 308are shown in FIG. 3. eNBs other than eNB 308 and base stations 310 and312 may have similar components. The components of eNB 308, discussed indetail below, may be included in one or more of the eNBs and/or basestations serving any of the cells of FIG. 1, including cell 102.

As shown, eNB 308 may include receiver/transmitter module 328.Receiver/transmitter module 328 may be configured for receiving signalsfrom and transmitting signals to other devices by wired or wirelessconnections. For example, receiver/transmitter module 328 may beconfigured to transmit and/or receive wireless signals to/from UE 314,NM apparatus 302, or other devices suitably configured for wirelesscommunications. In embodiments in which eNB 308 is configured forwireless communications, receiver/transmitter module 328 may include,for example, one or more directional or omni-directional antennas (notshown), as discussed above with reference to receiver/transmitter 322 ofNM apparatus 302.

eNB 308 may include an ESM IRP agent module 332. ESM IRP agent module332 may take any of the forms described above with reference to ESM IRPagent module 250 (FIG. 2). ESM IRP agent module 332 may be coupled withreceiver/transmitter module 328. Additional computing device components,such as one or more processors, memory, input/output (I/O) componentsand displays, may be included with eNB 308.

System 300 may include one or more UEs, such as UEs 314-320. One or moreof UEs 314-320 may include any of a number of wireless electronicdevices such as a desktop computer, a laptop computer, a handheldcomputer, a tablet computer, a cellular telephone, a pager, an audioand/or video player (e.g., an MP3 player or a DVD player), a gamingdevice, a video camera, a digital camera, a navigation device (e.g., aGPS device), a wireless peripheral (e.g., a printer, a scanner, aheadset, a keyboard, a mouse, etc.), a medical device (e.g., a heartrate monitor, a blood pressure monitor, etc.), and/or other suitablefixed, portable, or mobile electronic devices. In some embodiments, oneor more of UEs 314-320 may be a mobile wireless device, such as a PDA,cellular telephone, tablet computer or laptop computer. Each of UEs314-320 may include a number of components; for ease of illustration,only the components of UE 314 are shown in FIG. 3. UEs other than UE 314may have similar components.

As shown, UE 314 may include receiver/transmitter module 334.Receiver/transmitter module 334 may be configured for receiving wirelesssignals from and transmitting wireless signals to other devices. Forexample, receiver/transmitter module 334 may be configured to receivewireless signals from and transmit wireless signals to eNB 308 or otherdevices suitably configured for wireless communications.Receiver/transmitter module 334 may include, for example, one or moredirectional or omni-directional antennas (not shown), as discussedabove. Additional computing device components, such as one or moreprocessors, memory, input/output (I/O) components and displays, may beincluded with UE 314.

Referring now to FIG. 4, a flow diagram of example inter-RAT ESM process400 is illustrated, in accordance with various embodiments. Process 400may be executed by, for example, ESM IRP manager module 200 (FIG. 2) orany of the ESM IRP manager modules described herein. Process 400 may beexecuted by any of a number of other components of a wirelesscommunication system that implement some or all of the ESM IRP manageror agent functions described above. For example, process 400 may beexecuted by NM apparatus 302, eNB 308 or base station 310 (FIG. 3). Itmay be recognized that, while the operations of process 400 (and theother processes described herein) are arranged in a particular order andillustrated once each, in various embodiments, one or more of theoperations may be repeated, omitted or performed out of order. Forillustrative purposes, operations of process 400 may be described asperformed by ESM IRP manager module 200 (FIG. 2), but process 400 may beperformed by any suitably configured device.

Process 400 may begin at operation 402, in which ESM IRP manager module200 may identify a source cell that supports inter-RAT ES. In someembodiments, operation 402 may be executed by trigger module 202 (FIG.2) based on information received from ESM IRP agent 250 (e.g., thetraffic load of one or more NEs associated with ESM IRP agent 250 isbelow a threshold value). In some embodiments, the source cell may be ofa network of a first RAT that is a UTRAN or an E-UTRAN.

At operation 404, ESM IRP manager module 200 may identify a target cellproximate to the source cell (identified at operation 402). In someembodiments, a target cell may be adjacent to the source cell. In someembodiments, operation 404 may be executed by overlap module 204 (FIG.2) based on information received from ESM IRP agent 250. In someembodiments, the target cell may be of a network of a second RAT that isdifferent from the first RAT. For example, in some embodiments, thetarget cell may be a UTRAN cell (e.g., a frequency division duplex (FDD)mode cell, a low chip rate time division duplex (TDD) mode cell, or ahigh chip rate TDD mode cell). In some embodiments, the target cell maybe a GERAN cell.

At operation 406, ESM IRP manager module 200 may determine whether thetarget cell (identified at operation 404) is recommended to beconsidered as a candidate cell to take over coverage when the sourcecell is about to be transferred to an ESS. In some embodiments,operation 404 may be executed by overlap module 204 (FIG. 2) based oninformation received from ESM IRP agent 250. If yes, ESM IRP managermodule 200 may proceed to operation 408 and store a first value for anenergy-saving-coverage (ES-coverage) attribute corresponding to thetarget cell (such as the “IsCoveredBy” attribute discussed above withreference to Table 1). For example, the first value may be “yes.” Insome embodiments, the first value may be stored in a memory accessibleby overlap module 204, from which it may be later retrieved if thesource cell is triggered to activate an ESS. In some embodiments, theES-coverage attribute may be part of an information object class (IOC)containing radio network-related parameters. Process 400 may then end.

If ESM IRP manager module 200 determines at operation 406 that thetarget cell (identified at operation 404) is not recommended to beconsidered as a candidate cell to take over coverage when the sourcecell is about to be transferred to an ESS, ESM IRP manager module 200may proceed to operation 410 and determine whether the target cell isrecommended along with at least one other target cell to be consideredas an entirety of candidate cells to take over coverage when the sourcecell is about to be transferred to the ESS. In some embodiments,operation 404 may be executed by overlap module 204 (FIG. 2) based oninformation received from ESM IRP agent 250. If yes, ESM IRP managermodule 200 may proceed to operation 412 and store a second value,different from the first value (stored at operation 408), for theES-coverage attribute corresponding to the target cell (such as the“IsCoveredBy” attribute discussed above with reference to Table 1). Forexample, the second value may be “partial.” In some embodiments, asource cell that has a “partial” attribute with a target cell will havea “partial” attribute with at least one more target cell. Process 400may then end.

If ESM IRP manager module 200 determines at operation 410 that thetarget cell is not recommended along with at least one other target cellto be considered as an entirety of candidate cells to take over coveragewhen the source cell is about to be transferred to the ESS, ESM IRPmanager module 200 may proceed to operation 414 and store a third value,different from the first and second values (of operations 408 and 412,respectively), for the ES-coverage attribute corresponding to the targetcell if the target cell is not recommended to be considered as acandidate cell to take over coverage when the source cell is about to betransferred to an energy saving state (such as the “IsCoveredBy”attribute discussed above with reference to Table 1). For example, thethird value may be “no.” Process 400 may then end.

In some embodiments, multiple target cells may be identified atoperation 404. In such embodiments, operations 406-412 may be repeatedfor each of the multiple target cells. These operations may be repeatedin any of a number of orders (e.g., operation 406 may be performed foreach of the multiple target cells prior to performing another operationfor any of the multiple target cells, or operations 406-412 may beperformed for one cell, then repeated for a next cell, etc.).

Referring now to FIG. 5, a flow diagram of example inter-RAT ESM process500 executable by a UE (such as UE 314 of FIG. 3) is illustrated, inaccordance with various embodiments. Process 500 may be executed by, forexample, ESM IRP manager module 200 (FIG. 2) or any of the ESM IRPmanager modules described herein. Process 500 may be executed by any ofa number of other components of a wireless communication system thatimplement some or all of the ESM IRP manager or agent functionsdescribed above. For example, process 500 may be executed by NMapparatus 302, eNB 308 or base station 310 (FIG. 3). For illustrativepurposes, operations of process 500 may be described as performed by ESMIRP manager module 200 (FIG. 2), but process 500 may be performed by anysuitably configured device.

Process 500 may begin at operation 502, at which ESM IRP manager module200 may determine whether a source cell of a first RAT is triggered toactivate an ESS. In some embodiments, operation 502 may be executed bytrigger module 202 (FIG. 2A). In some embodiments, the network of thefirst RAT may be an E-UTRAN. In some embodiments, the network of thefirst RAT may be an UTRAN. The ESS may be a state in which somefunctions of the source cell are restricted in resource usage. In someembodiments, operation 502 may include determining when operatingconditions within the source cell have reached a trigger point (e.g., aload threshold for the source cell) at which an eNB is to activate anESS. In some embodiments, operation 502 may include determining that theeNB or other NE associated with the source cell supports inter-RAT ES.If ESM IRP manager module 200 determines “no” at operation 502, process500 may end.

If ESM IRP manager module 200 determines “yes” at operation 502, ESM IRPmanager module 200 may proceed to operation 504, and may determinewhether the source cell is partially overlapped by each of a pluralityof cells of one or more networks of one or more RATs different from thefirst RAT. In some embodiments, operation 504 may be executed by overlapmodule 204 (FIG. 2A). In some embodiments, operation 504 may includedetermining a set of ES-coverage attributes (e.g., as illustrated inTable 1) according to process 400 of FIG. 4 or another ES-coverageattribute determination process. In some embodiments, operation 504 mayinclude accessing and analyzing a set of stored ES-coverage attributes.In some embodiments, the network of the first RAT may be an E-UTRAN. Insome embodiments, the one or more networks of the one or more RATSdifferent from the first RAT may include one or more of a UTRAN or aGERAN. In some embodiments, the source cell may provide capacityenhancement to, but does not cover, an UTRAN or a GERAN coverage hole.If ESM IRP manager module 200 determines “no” at operation 504, process500 may end.

If ESM IRP manager module 200 determines “yes” at operation 504, ESM IRPmanager module 200 may proceed to operation 506 and determine whether acombination of the plurality of cells provides coverage of the sourcecell. In some embodiments, operation 506 may be executed by overlapmodule 204 (FIG. 2A). If ESM IRP manager module 200 determines “no” atoperation 506, process 500 may end. In some embodiments, a source cellmay be completely or partially covered by multiple target cells (e.g.,cells stored with a “yes” or other ES-coverage attribute value atoperation 408 of FIG. 4). In such embodiments, one or more of the targetcells may be chosen to compensate the source cell when it activates anESS (based on, e.g., the traffic load of the target cells).

If ESM IRP manager module 200 determines “yes” at operation 506, ESM IRPmanager module 200 may proceed to operation 508 and instruct the sourcecell to activate an ESS. In some embodiments, operation 508 may beexecuted by instruction module 206 (FIG. 2A). To mitigate servicedisruptions, the traffic handled by the source cell prior to activatingthe ESS may be handed over to the covering cells identified atoperations 502 and 504 (e.g., according to the current loads of thecovering cells).

At operation 510, ESM IRP manager module 200 may transmit a notificationmessage for display to a network operator (e.g., at a visual displaydevice) when the source cell has activated an ESS. In some embodiments,operation 510 may be executed by notification module 208 (FIG. 2A). Forexample, then ESM IRP manager module 200 is included in an eNB (such aseNB 308 of FIG. 3), operation 510 may including notifying an NMapparatus when the eNB has activated an ESS (e.g., based on a triggerpoint being reached per operation 502 and a combination of a pluralityof inter-RAT cells providing coverage of the source cell per operations504 and 506). In some embodiments, the notification of operation 510 mayinclude the identities of the plurality of cells whose combinationprovides coverage of the source cell (e.g., the cell identifiers of theplurality of cells).

At operation 512, ESM IRP manager module 200 may determine whether atraffic load on one or more of the plurality of cells exceeds athreshold. In some embodiments, operation 512 may be executed by one ormore of trigger module 202 and instruction module 206 (FIG. 2A). If ESMIRP manager module 200 determines “no” at operation 512, process 500 mayend.

If ESM IRP manager module 200 determines “yes” at operation 512, ESM IRPmanager module 200 may proceed to operation 514 and determine whetherthe plurality of cells are in a compromised operational status (e.g.,whether any of the cells have overloaded or failed). In someembodiments, operation 514 may be executed by one or more of triggermodule 202 and instruction module 206 (FIG. 2A). If ESM IRP managermodule 200 determines “no” at operation 514, process 500 may end.

If ESM IRP manager module 200 determines “yes” at operation 514, ESM IRPmanager module 200 may proceed to operation 516 and instruct the sourcecell to deactivate the ESS. In some embodiments, operation 516 may beexecuted by instruction module 206 (FIG. 2A). Process 500 may then end.

FIG. 6 is a block diagram of example computing device 600, which may besuitable for practicing various disclosed embodiments. For example, someor all of the components of computing device 600 may be used in any ofthe components of system 300 of FIG. 3. Computing device 600 may includea number of components, including one or more processor(s) 604 and atleast one communication chip 606. In various embodiments, processor 604may include a processor core. In various embodiments, at least onecommunication chip 606 may also be physically and electrically coupledto processor 604. In further implementations, communication chips 606may be part of processor 604. In various embodiments, computing device600 may include PCB 602. For these embodiments, processor 604 andcommunication chip 606 may be disposed thereon. In alternateembodiments, the various components may be coupled without theemployment of PCB 602. Communication chip 606 may be included in any ofthe receiver and/or transmitter modules described herein.

Depending on its applications, computing device 600 may include othercomponents that may or may not be physically and electrically coupled toPCB 602. These other components include, but are not limited to,volatile memory (e.g., dynamic random access memory 608, also referredto as DRAM), non-volatile memory (e.g., read-only memory 610, alsoreferred to as “ROM,” one or more hard disk drives, one or moresolid-state drives, one or more compact disc drives, and/or one or moredigital versatile disc drives), flash memory 612, input/outputcontroller 614, a digital signal processor (not shown), a cryptoprocessor (not shown), graphics processor 616, one or more antenna 618,touch screen display 620, touch screen controller 622, other visualdisplay devices (such as liquid-crystal displays, cathode-ray tubedisplays and e-ink displays, not shown), battery 624, an audio codec(not shown), a video codec (not shown), global positioning system (GPS)device 628, compass 630, an accelerometer (not shown), a gyroscope (notshown), speaker 632, camera 634, and a mass storage device (such as harddisk drive, a solid state drive, compact disc (CD), digital versatiledisc (DVD)) (not shown), and so forth. In various embodiments, processor604 may be integrated on the same die with other components to form aSystem on Chip (SoC).

In various embodiments, volatile memory (e.g., DRAM 608), non-volatilememory (e.g., ROM 610), flash memory 612, and the mass storage devicemay include programming instructions configured to enable computingdevice 600, in response to execution by processor(s) 604, to practiceall or selected aspects of the processes described herein. For example,one or more of the memory components such as volatile memory (e.g., DRAM608), non-volatile memory (e.g., ROM 610), flash memory 612, and themass storage device may include temporal and/or persistent copies ofinstructions that, when executed, enable computing device 600 to operatecontrol module 636 configured to practice all or selected aspects of theprocesses described herein. Memory accessible to computing device 600may include one or more storage resources that are physically part of adevice on which computing device 600 is installed and/or one or morestorage resources that is accessible by, but not necessarily a part of,computing device 600. For example, a storage resource may be accessed bycomputing device 600 over a network via communications chips 606.

Communication chips 606 may enable wired and/or wireless communicationsfor the transfer of data to and from computing device 600. The term“wireless” and its derivatives may be used to describe circuits,devices, systems, methods, techniques, communication channels, etc.,that may communicate data through the use of modulated electromagneticradiation through a non-solid medium. The term does not imply that theassociated devices do not contain any wires, although in someembodiments they might not. Many of the embodiments described herein maybe used with WiFi and 3GPP/LTE communication systems. However,communication chips 606 may implement any of a number of wirelessstandards or protocols, including but not limited to IEEE 702.20,General Packet Radio Service (GPRS), Evolution Data Optimized (Ev-DO),Evolved High Speed Packet Access (HSPA+), Evolved High Speed DownlinkPacket Access (HSDPA+), Evolved High Speed Uplink Packet Access(HSUPA+), Global System for Mobile Communications (GSM), Enhanced Datarates for GSM Evolution (EDGE), Code Division Multiple Access (CDMA),Time Division Multiple Access (TDMA), Digital Enhanced CordlessTelecommunications (DECT), Bluetooth, derivatives thereof, as well asany other wireless protocols that are designated as 3G, 4G, 5G, andbeyond. Computing device 600 may include a plurality of communicationchips 606. For instance, a first communication chip 606 may be dedicatedto shorter range wireless communications such as Wi-Fi and Bluetooth anda second communication chip 606 may be dedicated to longer rangewireless communications such as GPS, EDGE, GPRS, CDMA, WiMAX, LTE,Ev-DO, and others.

In various implementations, computing device 600 may be a laptop, anetbook, a notebook, an ultrabook, a smart phone, a computing tablet, apersonal digital assistant, an ultra mobile PC, a mobile phone, adesktop computer, a server, a printer, a scanner, a monitor, a set-topbox, an entertainment control unit (e.g., a gaming console), a digitalcamera, a portable music player, or a digital video recorder. In furtherimplementations, computing device 600 may be any other electronic devicethat processes data.

Computer-readable media (including non-transitory computer-readablemedia and/or tangible computer-readable media), methods, systems anddevices for performing the above-described techniques are illustrativeexamples of embodiments disclosed herein. Additionally, other devicesmay be configured to perform various disclosed techniques.

The following paragraphs describe examples of various embodiments. Invarious embodiments, one or more non-transitory computer-readable mediahas instructions that, when executed, cause an IRP manager module of amanagement apparatus to: identify a source cell that supports inter-RATenergy saving, the source cell of a network of a first RAT that is aUTRAN or an E-UTRAN; identify a target cell that is proximate to thesource cell, the target cell of a network of a second RAT that isdifferent from the first RAT; store a first value for anenergy-saving-coverage attribute corresponding to the target cell if thetarget cell is recommended to be considered as a candidate cell to takeover coverage when the source cell is about to be transferred to anenergy saving state; and store a second value, different from the firstvalue, for the energy-saving-coverage attribute corresponding to thetarget cell if the target cell is recommended along with at least oneother target cell to be considered as an entirety of candidate cells totake over coverage when the source cell is about to be transferred tothe energy saving state. In some embodiments, the management apparatusis a network management (NM) apparatus. In some embodiments, the targetcell is a UTRAN cell. In some embodiments, the UTRAN cell is an FDD modecell, a low chip rate TDD mode cell, or a high chip rate TDD mode cell.In some embodiments, the target cell is a GERAN cell. In someembodiments, the first value is yes and the second value is partial. Insome embodiments, the one or more non-transitory computer-readable mediafurther includes instructions that, when executed, cause the IRP managermodule to store a third value, different from the first and secondvalues, for the energy-saving-coverage attribute corresponding to thetarget cell if the target cell is not recommended to be considered as acandidate cell to take over coverage when the source cell is about to betransferred to an energy saving state nor recommended along with atleast one other target cell to be considered as an entirety of candidatecells to take over coverage when the source cell is about to betransferred to the energy saving state. In some embodiments, theenergy-saving-coverage attribute is part of an information object classcontaining radio network-related parameters. Some embodiments of one ormore computer readable media include various combinations of theforegoing.

In various embodiments, an NM apparatus includes: a trigger module todetermine that a source cell of a network of a first RAT is triggered toactivate an energy saving state; an overlap module to determine that thesource cell is partially overlapped by each of a plurality of cells ofone or more networks of one or more RATs different from the first RAT;and an instruction module to instruct the source cell to activate theenergy saving state when a combination of the plurality of cellsprovides coverage of the source cell. In some embodiments, the networkof the first RAT is an E-UTRAN. In some embodiments, the one or morenetworks of one or more RATS different from the first RAT include one ormore of a UTRAN or a GERAN. In some embodiments, the source cellprovides capacity enhancement to, but does not cover, a UTRAN coveragehole or a GERAN coverage hole. In some embodiments, the instructionmodule is further to instruct the source cell to deactivate the energysaving state after instructing the source cell to activate the energysaving state. In some embodiments, the instruction module is to instructthe source cell to deactivate the energy saving state based on a trafficload of one or more of the plurality of cells or based on an operationalstatus of one or more of the plurality of cells. In some embodiments,the plurality of cells include a first cell and a second cell, a firstportion of the source cell is covered by the first cell but not thesecond cell, a second portion of the source cell is covered by thesecond cell but not the first cell, and a third portion of the sourcecell is covered by the first cell and the second cell. In someembodiments, the NM apparatus further includes a notification module totransmit a notification message for display to a network operator whenthe source cell has activated the energy saving state. In someembodiments, the NM apparatus further includes a visual display deviceto display the notification message transmitted by the notificationmodule. In some embodiments, the energy saving state includes a state inwhich some functions of the source cell are restricted in resourceusage. Some embodiments of an NM apparatus include various combinationsof the foregoing.

In various embodiments, an eNB, serving a source cell of a network of afirst RAT, includes: a trigger module to determine when operatingconditions within the source cell have reached a trigger point at whichthe eNB is to activate an energy saving state; an overlap module todetermine that the source cell is partially overlapped by each of aplurality of cells of one or more networks of one or more RATs differentfrom the first RAT; and a notification module to notify an NM apparatuswhen the eNB has activated the energy saving state, the eNB entering theenergy saving state based on the trigger point being reached and acombination of the plurality of cells providing coverage of the sourcecell. In some embodiments, the eNB further includes an instructionmodule to instruct the eNB to activate the energy saving state when thetrigger point is reached and a combination of the plurality of cellsprovide coverage of the source cell. In some embodiments, theinstruction module is further to instruct the eNB to deactivate theenergy saving state. In some embodiments, the trigger module is furtherto determine that the eNB supports inter-RAT energy saving, prior toinstruction of the eNB by the instruction module. In some embodiments,the trigger point includes a load threshold crossing value. In someembodiments, the network of the first RAT includes a UTRAN or anE-UTRAN. In some embodiments, the network of the first RAT includes anE-UTRAN and the one or more networks of the one or more RATs differentfrom the first RAT include a UTRAN or a GERAN. In some embodiments, thenotification module is further to notify the NM apparatus of identifiersof the plurality of cells whose combination provides coverage of thesource cell. In some embodiments, the plurality of cells providescomplete coverage of the source cell. Some embodiments of an eNB includevarious combinations of the foregoing.

Although certain embodiments have been illustrated and described hereinfor purposes of description, a wide variety of alternate and/orequivalent embodiments or implementations calculated to achieve the samepurposes may be substituted for the embodiments shown and describedwithout departing from the scope of the present disclosure. Thisapplication is intended to cover any adaptations or variations of theembodiments discussed herein. Therefore, it is manifestly intended thatembodiments described herein be limited only by the claims.

Where the disclosure recites “a” or “a first” element or the equivalentthereof, such disclosure includes one or more such elements, neitherrequiring nor excluding two or more such elements. Further, ordinalindicators (e.g., first, second or third) for identified elements areused to distinguish between the elements, and do not indicate or imply arequired or limited number of such elements, nor do they indicate aparticular position or order of such elements unless otherwisespecifically stated.

1-15. (canceled)
 16. An apparatus to be employed as an integrationreference point (IRP) manager by a network manager (NM), the apparatuscomprising processor circuitry coupled with memory circuitry, the memorycircuitry having instructions, which when executed by the processorcircuitry, cause the processor circuitry to: determine that a sourcecell of a network of a first radio access technology (RAT) is triggeredto activate an energy saving state; identify a plurality of candidatecells for an inter-RAT handover from the source cell, each candidatecell of the plurality of candidate cells partially covering the sourcecell, each candidate cell of the plurality of candidate cells associatedwith a different RAT than a RAT of the source cell; determine that theplurality of candidate cells collectively cover the entirety of thesource cell; instruct the source cell to activate the energy savingstate in response to determining that the plurality of candidate cellscollectively cover the entirety of the source cell; and perform theinter-RAT handover from the source cell to the plurality of candidatecells.
 17. The apparatus of claim 16, wherein the instructions in thememory circuitry are further configured to cause the processor circuitryto determine that the source cell supports inter-RAT energy saving, andwherein identifying the plurality of candidate cells comprisesidentifying the plurality of candidate cells in response to determiningthat the source cell supports inter-RAT energy saving.
 18. The apparatusof claim 16, wherein the instructions in the memory circuitry arefurther configured to cause the processor circuitry to store a “partial”value for an IsEScoveredBy attribute corresponding to each candidatecell of the plurality of candidate cells.
 19. The apparatus of claim 18,wherein the IsEScoveredBy attribute is part of an information objectclass (IOC) containing radio network-related parameters.
 20. Theapparatus of claim 16, wherein the instructions in the memory circuitryare further configured to cause the processor circuitry to instruct thesource cell to deactivate the energy saving state based on a trafficload of one or more candidate cells of the plurality of candidate cellsor based on an operational status of one or more candidate cells of theplurality of candidate cells.
 21. The apparatus of claim 16, wherein theplurality of candidate cells comprises a first candidate cell and asecond candidate cell, and wherein a first portion of the source cell iscovered by the first candidate cell but not the second candidate cell, asecond portion of the source cell is covered by the second candidatecell but not the first candidate cell, and a third portion of the sourcecell is covered by the first candidate cell and the second candidatecell.
 22. The apparatus of claim 16, wherein the RAT of the source cellis an evolved universal terrestrial radio access network (E-UTRAN). 23.The apparatus of claim 22, wherein the RATs of the plurality ofcandidate cells comprise one or more of a universal mobiletelecommunications system terrestrial radio access network (UTRAN) or aglobal system for mobile communications enhanced data rates for globalsystem for mobile communication evolved radio access network (GERAN).24. The apparatus of claim 16, wherein the instructions in the memorycircuitry are further configured to cause the processor circuitry to:identify one or more other cells proximate the source cell, the one ormore other cells each associated with a different RAT than the RAT ofthe source cell; and store a “no” value for the IsEScoveredBy attributecorresponding to each of the one or more other cells.
 25. The apparatusof claim 16, wherein the instructions in the memory circuitry arefurther configured to cause the processor circuitry to instruct thesource cell to activate the energy saving state by instructing thesource cell to transition to a low power state.
 26. The apparatus ofclaim 16, wherein the instructions in the memory circuitry are furtherconfigured to cause the processor circuitry to determine that the sourcecell is triggered to activate the energy saving state by determiningthat a traffic load of the source cell is below a threshold value. 27.One or more non-transitory computer-readable media having instructionsthat, when executed, cause an integration reference point (IRP) managermodule of a network manager (NM) to: determine that a source cell of anetwork of a first radio access technology (RAT) is triggered toactivate an energy saving state; identify a plurality of candidate cellsfor an inter-RAT handover from the source cell, each candidate cell ofthe plurality of candidate cells partially covering the source cell,each candidate cell of the plurality of candidate cells associated witha different RAT than a RAT of the source cell; determine that theplurality of candidate cells collectively cover the entirety of thesource cell; instruct the source cell to activate the energy savingstate in response to determining that the plurality of candidate cellscollectively cover the entirety of the source cell; and perform theinter-RAT handover from the source cell to the plurality of candidatecells.
 28. The one or more non-transitory computer-readable media ofclaim 27, wherein the instructions are further configured to cause theIRP manager module to determine that the source cell supports inter-RATenergy saving, and wherein identifying the plurality of candidate cellscomprises identifying the plurality of candidate cells in response todetermining that the source cell supports inter-RAT energy saving. 29.The one or more non-transitory computer-readable media of claim 27,wherein the RAT of the source cell is an evolved universal terrestrialradio access network (E-UTRAN).
 30. The one or more non-transitorycomputer-readable media of claim 29, wherein the RATs of the pluralityof candidate cells comprise one or more of a universal mobiletelecommunications system terrestrial radio access network (UTRAN) or aglobal system for mobile communications enhanced data rates for globalsystem for mobile communication evolved radio access network (GERAN).31. The one or more non-transitory computer-readable media of claim 27,wherein the instructions are further configured to cause the IRP managermodule to: identify one or more other cells proximate the source cell,the one or more other cells each associated with a different RAT thanthe RAT of the source cell; and store a “no” value for the IsEScoveredByattribute corresponding to each of the one or more other cells.
 32. Amethod of energy saving employed by an integration reference point (IRP)of a network manager (NM), the method comprising: determining, by theIRP, that a source cell of a network of a first radio access technology(RAT) is triggered to activate an energy saving state; identifying, bythe IRP, a plurality of candidate cells for an inter-RAT handover fromthe source cell, each candidate cell of the plurality of candidate cellspartially covering the source cell, each candidate cell of the pluralityof candidate cells associated with a different RAT than a RAT of thesource cell; determining, by the IRP, that the plurality of candidatecells collectively cover the entirety of the source cell; instructing,by the IRP, the source cell to activate the energy saving state inresponse to determining that the plurality of candidate cellscollectively cover the entirety of the source cell; and performing, bythe IRP, the inter-RAT handover from the source cell to the plurality ofcandidate cells.
 33. The method of claim 32, further comprisingdetermining, by the IRP, that the source cell supports inter-RAT energysaving, and wherein identifying the plurality of candidate cellscomprises identifying the plurality of candidate cells in response todetermining that the source cell supports inter-RAT energy saving. 34.The method of claim 32, further comprising storing, by the IRP, a“partial” value for an IsEScoveredBy attribute corresponding to eachcandidate cell of the plurality of candidate cells.
 35. The method ofclaim 34, further comprising: identifying, by the IRP, one or more othercells proximate the source cell, the one or more other cells associatedwith a different RAT than the RAT of the source cell; and storing, bythe IRP, a “no” value for the IsEScoveredBy attribute corresponding toeach of the one or more other cells.